Material handling system

ABSTRACT

A dispensary type warehousing system featuring palletizing vehicle providing a mobile platform work station, together with pick aisles sufficiently narrow so that all merchandise to be picked is within the picker&#39;&#39;s reach without the need for leaving the vehicle. The invention makes it unnecessary for the picker to dismount from the mobile platform to perform his task, and this in turn permits partial automation of the vehicle control equipment as shown.

iJnited States-Patent 1191 Lapham July 23, 1974 [54] MATERIAL HANDLINGSYSTEM 1,179,513 10/1964 061m 2l4/16.4 A [76] Inventor: sidmy Lapham,2324 Creek 1333:31 1? 2/1323 214/l6.4 A

Dr. Manor No. 3, Walnut Creek, Calif. 94529 Primary Examiner-Albert J.Makay [22] Filed June 1972 Assistant Examiner-R. B. Johnson [21] Appl.N0.: 266,219 Attorney, Agent, or Firm-Phillips, Moore, Weissen- I bergerLempio & Strabala [52] US. Cl. 214/16 B, 2l4/16.4 A, 180/25 R, 180/14,254/8 R' 51 Int. Cl. 365g 1/04 ABS A T [58] meld of Search IIII 214/164A, A dispensary type warehousing system featuring palletizing vehicleproviding amobile platform work stales sufficient] narrow so [56]References Cited together wlt.h plck y that all merchandise to be picked1s within the plckers UNITED STATES PATENTS reach without the need forleaving the vehicle. The in- Bear R vention make unne essary for pickerto disg f g mount from the mobile Platform to perform his task, erg onerC 8. 3,52e,327 9/1970 Atwater 2141164 A g ggg z szgmg of the FOREIGNPATENTS OR APPLICATIONS 276,241 11/1969 Austria 214/670 5 Claims, 17Drawing Figures Li L! ///4 PAlEmmJuLzalsm SHEET 1 0F 6 nm wl TE moEi iPATENTEBJULZSISM FIG SHEET 0F 6 7 FEG 4 INVENTOR. SlDNEY o. LAPHAMPATENTEU I- 2 3 I974 saw u or g mamma 3.885.130

SHEET 5 BF 6 INVENTOR- F 9 SIDNEY'D. LAPHAM ATTORNEYS 1 MATERIALHANDLING SYSTEM BACKGROUND OF THE INVENTION Distribution warehouses forgroceries and similar merchandise lines essentially carry out thefollowing functions: (a) pallets of merchandise are received fromindividual suppliers; (b) the merchandise is stored out of the weatherpending distribution; (c) portions of pallets (e.g., one or more casesof merchandise) are picked and combined with other cases to form newpallets containing a mixture of products; and (d) the mixed pallets areshipped to the retain stores.

In a conventional grocery warehouse, three types of storage areprovided: (I) block storage, where pallets holding a large quantity ofincoming merchandise are stacked in a storage area on top of one anotheras high as a fork lift truck can reach; (II) pick storage, where two orthree single-product pallets are stored in a pick area on the floor oron individual shelves within the pickers reach for picking a productmix;and (II) stock storage, where two or three single product pallets arestored in the pick area-on a shelf or tier above the pickers reach, forthe purpose of replenishing the pick stock as it becomes exhausted.

In order to move merchandise from the receiving dock to the shippingdock, the following operations are involved in a conventional warehouse:(l) incoming pallets, which are commonly about 2 to 4 feet in height arestacked two or three high to form a pallet stock approximately 6 to 8feet in height, which a fork lift truck can handle as a unit; (2) thepallet stacks are moved from the receiving area to the appropriate blockstorage bay; (3) individual pallet stacks are moved from the blockstorage bay to the stock storage shelf of the appropriate pick bay; (4)individual pallets are moved from the stock storage shelf to the pickshelves or floor below; (5) the products are picked and assembled intomixed-product pallets; and (6) the mixed-product pal- Ietsare moved tothe shipping area.

Because steps (1) through (4) above involve vertical movement of palletsat substantial heights above the floor, they require the use of forklift trucks. These are expensive, cumbersome vehicles which arerelatively slow and difficult to operate, and which require a great dealof maneuvering room. Inasmuch as steps (3) and (4) require the use of afork lift truck in the pick area aisles, the minimum aisle width for thepick area of a conventional warehouse is about 12 feet.

The most common pallet size in the grocery industry is about 48 inches X40 inches, with the height of the pallet depending on the package sizeof the product involved. In the block storage area, where all handlingis done by fork lift truck, it is practical to store pallets two orsometimes even three deep transversely to the aisle. In the pick area,however, the reach limitation of the picker dictates storage only onepallet deep.

In the conventional warehousing system, the racks in the pick area mustof necessity be supported by vertical supports or legs at fairly closeintervals. In addition, the positioning tolerances for pallets handledby fork lift trucks require about 6 inches between pallets, so that theconventional system requires about 48 inches per pallet space (the longdimension of the pallet being transverse to the aisle when stored).

A conventional warehouse bay is feet X 40 feet in size. With the 12 footaisles of the conventional system mally be allocated to any one product.

Experience has shown that the majority of products in a typical chainstore warehouse are picked at the rate of about 60 to 120 cases per day.With the reach of an average man being about 6 feet 6 inches, and about6 inches being consumed by the shelf and shelf clearance in theconventional pick storage, one pallet space of the conventional systemcan accommodate two pallets per tier of 40 cubic feet or less each; inother words, a total or no more than cubic feet of pick storage product.This means that more often than not, the pick storage of any givenproduct is exhausted before the end of the day, and a fork lift truckhas to be called in to replenish the pick storage from the stockstorage.

Aside from creating movement problems for the picker due to the forklifts blocking the pick aisle during the replenishing operation, theconventional system often results either in a delay between exhaustionand replenishing, or in replenishing before all cases of the producthave been picked from pick storage. In the lat-- ter event, when thepick storage is replenished with full pallets, leftover cases of productare frequently placed on the floor in front of the pick storage pallet,where they obstruct the aisle.

A further disadvantage of the conventional system is that the picker,who works on the floor, cannot load a mixed pallet on a cart to morethan about 6 feet from the floor without exceeding his reach. Inasmuchas the bed of the cart is typically about 2 feet off the floor, themaximum mixed pallet height is about 4 feet.

Experience has shown that in a conventional warehouse, using the mostefficient type of conventional picking equipment, the average pickerpicks on the order of 1,000 cases of product per 8 hour shift. Inasmuchas a warehouse of the size contemplated herein can accommodate no morethan about pickers per shift, lest they get in each others way, theoutput capacity of the warehouse is about 100,000 cases per shift. Itshould be noted that each shift requires its own complement ofmachinery, as the batteries of most electrically driven warehousingmachinery are designed for 8 hour work, 16 hour charge cycles.

In addition to the replenishing which is done during the regular workshifts, it is common practice in grocery warehouses to replenish thepick storage and stock storage during the night, when the fork liftoperators can work without interfering with the pickers.

SUMMARY OF THE INVENTION In accordance with the invention, the outputcapacity which provides an elevated work platform directly adjacent tothe pallets in pick storage, and a recessed mixed pallet supportsurrounded by the elevated platform on three sides and located below thelevel of the platform. By eliminating the stock storage, the system ofthis invention eliminates the use of fork lift trucks in the pick area.As a result, the pick aisles can be made much narrower; narrow enough,in fact, to be scarcely wider than the width of the palletizing vehicle.

The elimination of stock storage further reduces handling of themerchandise by eliminating handling step (3) described above. Inaddition, the movement of single-product pallets from the block storagearea to the pick area can now be performed by small, highlymaneuverable, and inexpensive conventional pallet transporters insteadof fork lift trucks. Furthermore, the lack of height restrictions due tothe rack structure in pick storage and the added reach provided by theelevated platform of the palletizing vehicle makes practical the use ofsingle-product pallets 7 feet high, so that step (I), the stacking step,can also be eliminated.

The maneuverability of the pallet transporters permits a reduction ofthe space between pallets in pick storage from 6 inches to about 2inches. The elimination of the racks also eliminates the spacerequirement for the rack supports. As a result, a typical 60 foot X 40foot bay contains 102 pallet spaces in the system of the invention, eachof which can accommodate more than 100 cubic feet of merchandise. Thetotal pick storage capacity of the bay is thus increased to over 100,000cubic feet from the less than 4,800 cubic feet of the conventionalsystem.

It follows from the more than doubling of the pick storage capacity thatfor essentially all except fairly slow-moving products, the palletspreviously stored in stock storage can now be stored in pick storage ona two-pallet-spaces-per-product basis (dual pallet storage) for mostproducts. The more than 200 cubic feet of each product which thus becomeavailable to the picker represent a quantity well in excess of what canbe expected to be picked in the course ofa day. Thus, replenishment ofpick storage during the picking shift is eliminated except on a fewoccasions. Likewise, the resultant replacement of pallets only when they.are empty eliminates the problem of leftover cases.

The palletizing vehicle of this invention holds the bottom of the mixedpallet being assembled just clear of the floor. With the picker standingon the elevated platform of the vehicle, he can easily assemble a 7 footmixed pallet suitable for loading into a truck without restacking. Thepalletizing vehicle can deposit the completed pallet on the floor at theloading dock, where it can be picked up when desired with a pallettransporter and loaded into the truck without the assistance of a forklift truck. By contrast, in the conventional system, fork lift truckswere usually required for lifting completed pallets off the palletizingcarts and stacking them in the truck, a process which often congestedthe loading area.

Specifically, the palletizing vehicle of this invention includescombined steering and control means for operating the vehicle andbatteries for supplying motive power for the vehicle. An H-shapedwalkway is disposed on the vehicle with the motor and batteriesoccupying the forward end between the front legs of the H- shapedwalkway, with a low pick-up fork disposed at the rearward end betweenthe rear legs of the H-shaped walkway and extending past the rear of thevehicle. In this manner, mixed pallets can be readily built up on thevehicle while the picker, using the storage system of this invention,never needs to leave the vehicle. A pair of such vehicles may be shippedas a generally compact unit, thus lowering the shipping costs thereof.

It is therefore the object of this invention to provide a warehousingsystem capable of approximately doubling the output capacity per man-dayof conventional warehouses while substantially reducing machinery andfixture costs.

It is another object of this invention to provide a palletizing vehiclespecially adapted for the efficient palletizing of a product mix.

It is still another object of the invention to provide a merchandisestorage pattern for grocery warehouses and the like which, when used inconjunction with the palletizing vehicle of this invention, greatlyspeeds up the picking operation.

It is a further object of this invention to provide a palletizingvehicle of the type described which, in addition to driving and controlmeans, features a platform forming elevated walkways along the sides ofthe pallet, a pallet support surrounded on three sides by said platformand positioned substantially below the level of said platform, and meansfor moving the pallet support between a position where it holds thepallet slightly off the ground and a position where it deposits thepallet on the floor so that it can be disengaged from the pallet.

It is a still further object of the invention to provide a palletizingvehicle of the type described in which the pallet support is locatedinside the polygon defined by its walkways. I

BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1a through 1d are elevationalviews of warehouse storage systems contrasting a prior art system withthe system of my invention;

FIGS. 2a through 2d are top plan views of the systems of FIGS. lathrough 1d, respectively;

FIG. 3 is a vertical view of a palletizing vehicle in accordance with myinvention to be used in the system of FIGS. 1 and 2;

FIG. 4 is a top plan view of the vehicle of FIG. 3; FIG. 5 is a frontview of the vehicle of FIGS. 3 and FIG. 6 is a vertical detailed view ofa portion of the vehicle of FIGS. 3-5 with portions thereof in sectionand other portions omitted for convenience of illustration;

FIG. 7 is a top plan view of a portion of the view of FIG. 6;

FIG. 8 is a vertical view of a pair of the vehicles of FIGS. 3 through 7mounted for shipment thereof;

FIG. 9 is a top plan view of the mounted vehicles of FIG. 8; and

FIGS. 10 and 11 illustrate a charging and guiding system for the vehicleof this invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT The basic concept of theinvention is the creation of a movable work station for the picker in adistribution warehouse, and to bring the merchandise within the reach ofa picker working on the movable work station so that he never need leaveit in the course of his work. In order to achieve this objective, theinvention encompasses not only the mechanics of the movable work stationitself, but also the particular physical arrangement of the merchandisein the pick bays of the warehouse which makes it possible to bring themerchandise within the pickers reach.

The advantage achieved by the invention is the elimination of thetime-consuming walking to and from the palletizing vehicle or workstation in conventional distribution warehouses. The advantage isachieved by sacrificing the utilization of air rights in the pick baysso as to eliminate the need for mechanical vertical movement ofmerchandise in the pick bays, which underlies the need for the wide pickaisles of the conventional distribution warehouse that generate thewalking requirement and other inefficiencies and safety hazardseliminated by this invention.

Thus, the present invention, though at first glance highly wasteful ofwarehouse space, in fact cuts warehousing costs about in half by makingpossible highly efficient utilization of floor space, manpower, andequipment without substantially reducing the total storage capacity ofthe warehouse.

FIGS. 1a and 2a show an elevation and plan view, respectively, of thepresently conventional grocery warehouse arrangement. The most commonpallet size is 40 inches X 48 inches, with 40 inches (pallets 102 inFIG. 1a) and 18 inches (pallets 104 in FIG. la) being common palletheights. In the conventional pick area arrangement shown in FIGS. la and2a, pallets are stored one deep along each side of aisles 106, which areabout 12 feet wide toprovide maneuvering room for fork lift trucks. Theneed for this maneuvering room arises from the storage of replenishmentstock pallets 108 out of the pickers reach on the shelves 110 of racksextending alongside the aisles 106 throughout their entire lengths.

The pick storage is done partly on the floor (as for pallets 112, 114)and partly on lower shelves (116 or 118, 120) within the reach of thepicker. As the pick storage is exhausted, it is replenished by movingthe pallets 108 down to the pick storage locations by means feet highand generally consist of two inch pallets or four 18 inch pallets, eachincluding a wooden pallet base typically about 5 inches thick. Each ofthe pallet stacks 124 represents one normal fork lift load. The palletstacks 124 are then in turn stacked in the block storage areas in bayarrangements such as shown in FIGS. lb and 2b.

Considering that pallets moved by fork lift trucks require 8 inchclearances between pallets, a typical pallet space in FIGS. 2a and 2b is4 feet X 4 feet in size. Using the more common 40 inch high pallet as astandard and assuming, conservatively, that the product is stacked 36inches high on the 40 inch pallets (the other.4

inches being taken up by the wooden pallet base), a pick area bay of theconventional warehouse of FIGS. la and 2a can accommodate 9,600 cubicfeet of product (60 spaces X 4 pallets per space X 40 cubic feet ofproduct per pallet), of which 4,800 cubic feet (two pallets per space)are available for picking when the 40 foot X 60 foot bay of FIG. 2a isfull. Thus, the system of this invention results in far betterutilization of the cubic space of the warehouse than does theconventional system.

The block storage layout of FIGS. lb and 2b, which is the most practicalconventional layout, and which is retained in the system of thisinvention, typically accommodates, within the reach of a fork lifttruck, 23,760 cubic feet of product, assuming again the use of 40 inchhigh pallets.

In accordance with the invention, the pick area storage system ischanged from that shown in FIGS. la and 2a to that shown in FIGS. 1c and2c. The arrangement of FIG. 2c still has three pick aisles 126, butunlike the aisles 106 of FIG. 2a, the aisles 126 are disposed lengthwiseof the bay and are much narrower preferably only about 64 inches wide.

Inasmuch as the narrow width of the aisles 126 precludes the use of forklift equipment, pallets in the pick area of FIGS. 1c and 2c can only bestored on the floor, not on shelves. Placement of the pallets in thiscase is done by pallet transporters (not shown), which are low, easilymaneuverable, small powered vehicles capable of moving pallets from oneplace to another but not of lifting them more than a few inches off thefloor.

The maneuverability of the pallet transporters and the fact that allpallets are placed on the floor permits fast, accurate placement ofpallets in the pick area with minimum clearance (as little as 2 inches)between pallets. As a result, 17 pallet spaces 128 are available in thesystem of FIG. 20 on each side of the aisle 126, for a total of 102pallet spaces per pick bay. In addition, if one of the short sides ofthe bay of FIG. 2c adjoins a cross-aisle 130 (i.e., a wide aisle fortravel to and from the block storage and shipping areas), rack storagelike that of FIG. 1a is possible along cross-aisle 130, preferably forslower-moving types of products which do not require frequentreplenishment. For this purpose, racks 132 may be provided withappropriate shelves 134 located sufficiently high (e.g., 8 feet) abovethe floor to allow the palletizing vehicle of this invention (See FIG.1d) to pass under them.

As the pallets 136 stored on shelf 134 are needed, they can be placed inthe pallet spaces underneath the rack 132 with a fork lift truck, andcan then be picked from the aisles 126 like the other pallets in thepick area of FIG. 2c.

The fact that aisles 126 are narrow enough to clear the palletizingvehicle 13 shown in the enlarged views 1d and 2d of FIGS. 1c and 20,respectively, by only about 4 inches on each side makes it possible forthe picker 140 to remain on the elevated platform of the vehicle 13 atall times and thus extend his reach to some 7% feet from the floor.Thus, even assuming the use of a heavy 6 inch-thick pallet base 142 inthe system of this invention, the product can be stacked 7 feet high onthe pallet base 142 without exceeding the reach of picker 140. Assuming(for reasons discussed below) that the product is stacked, on theaverage, only 6% feet high on each pallet base, the storage capacity(even in the absence of racks 132) of the pick bay of FIGS. 1c and 2c is8,850 cubic feet of product all of it available for picking.

In a typical grocery warehouse of manageable size, the number ofproducts handled is such that only one pick area pallet space can beallocated to each of the most commonly used products. However, in orderto follow a first-in, first-out policy of use, it is necessary to placetwo pallets of each product side by side so that one can be replacedwhile the other is being picked. This is the reason why, in theconventional system, pallets 112 and 116 are different products, whereaspallet 112 and the pallet (not shown) next to it on the same aisle arethe same product. Consequently, particularly since some space has to beleft between the top of each pallet and the underside of the shelf aboveit, the pallet height in the conventional system is limited to around 40inches.

In the system of this invention, the circumstances dictating the 40 inchpallet height restriction are absent. Consequently, the only restrictionon pallet height is the vertical clearance of the truck door usually 7/2 feet. Hence, the maximum practical pallet height is about 7 feetincluding the pallet base, or roughly the aforementioned 6% feet ofproduct. Inasmuch as the pick bay of FIG. 20 has, however, almost twiceas many pallet spaces as the conventional pick bay of FIG. 2a, it ispractical to use two pallet spaces, on the average, for each product.Thus, in FIG. 2d, pallets 114 and 146 may be one product, and pallets148, 150 another. It will be seen that whereas, in the conventionalsystem, the picker had no more than 80 cubic feet of product availableto him at any time, the picker in the system of the invention has asmuch as 200 odd cubic feet of the same product at his disposal enough topick more than twice as long between replenishings.

Time-and-motion studies have established that the system of thisinvention approximately doubles the pick rate per man-day of the pickingcrew, even without the use of the automated equipment of FIGS. 10 and11. In addition, it substantially eliminates the use ofa replenishingcrew during picking shifts and the consequent interference with thepickers. Also, by making possible the use of 7 foot pallets, thereceiving area stacking step is eliminated, as is the double movementbetween block storage and pick storage. Finally, the use of 7 footpallets increases the capacity of the average block storage bay fromabout 23,760 to about 25,800 cubic feet of product.

Conventional warehousing systems use palletizing carts whose bed isabout 2 feet off the floor. Assuming a 6 foot reach, the picker cannotconveniently assemble mixed pallets higher than 4 feet in theconventional system. Thus, the conventional system usually fails toeffectively utilize the 7% foot interior height of conventional trucks.By contrast, the low position of the pallet supporting forks 36 (FIG. 4)in the vehicle 13 of this invention, together with the height of theplatform 17-18-19 and the pads 22, 23, allow a mixed pallet to bestacked to the full 7 foot-plus height which the truck can accommodate.Inasmuch as the palletizing vehicle 13 can deposit the mixed pallet onthe floor of the ship-- ping area, and a pallet transporter can move itfrom there into the truck, the use of a fork lift truck at the shippingarea is eliminated by the system of this invention.

Referring now to FIGS. 3 and 4, vehicle 13 includes a first generallyhorizontal supporting surface in the form of an H-shaped walkway l6.Walkway 16 includes a first centrally located section 17 normal to apair of second and third side sections 18 and 19. As can be seen in FIG.4, sections 18 and 19 extend from the front to the rear of vehicle 13.At the front of vehicle 13, sections 18 and 19 include a pair of frontsections 20 and 21, respectively. In this manner, an H-shaped walkway 16is formed and an operator can walk almost com pletely about theperiphery of vehicle 13 and across the short axis thereof (i.e., firstsection 17).

One or more horizontal levels, such as a second horizontal level, isformed on vehicle 13 by means of a pair of wheel covers 22 and 23.Covers 22 and 23 are integrally connected to and extend upwardly fromsections 18 and 19, respectively, at the rear thereof. As can clearly beseen in FIG. 3, covers 22 and 23, preferably at the same horizontallevel, form a second or upper support surface vertically spaced from thefirst support surface of vehicle 13 (i.e., walkway 16). A pair of rearwheels 24 and 25 are journalled for rotational movement in covers 22 and23, respectively.

As shown in dotted lines in FIGS. 4 and 5, a conventional battery-drivenmotor 28 is disposed in a motor housing 29 which is centrally located atthe forward end of vehicle 13 and extends from the supporting surface ofvehicle 13. A single front wheel 30 is preferably driven by motor 28 byany suitable drive means. Wheel 30- is steered by means of a steeringwheel 31 connected by shaft 32 which extends out of the top of motorhousing 29. Steering wheel 31 may also be removable for shippingpurposes. Finally, housing 29 includes a suitable console 33 or the likefor operating motor 28.

Any suitable motive means may be used for operating vehicle 13.Thus,console 33, motor 28, drive wheel 30, steering wheel 31 and shaft 32 mayall be conventional mechanisms or the like for propelling and steeringvehicle 13. However, in accordance with the teachings of my invention,motor 28 is electrically driven by suitable batteries or the like.

Thus, as shown in FIGS. 3 through 5, a pair of battery housings 34 and35 are disposed at the forward end of vehicle 13 and on each side ofmotor housing 29 (the batteries themselves not being visible). Suchrelatively large housings are required in view of the tremendous amountof electrical power required to operate motor 28 and thus render vehicle13 entirely self-contained. These battery housings 34 and 35 (and, ofcourse, the batteries themselves) may be removable from vehicle 13 andshipped separately for reasons to be discussed hereinbelow.

Referring once again to FIG. 4, the fork 36 is disposed at the rear ofvehicle 13 and extends underneath walkway l6 and outwardly a shortdistance past the rear of vehicle 13. That is, fork 36 is generallyparallel to and spaced from sections 18 and 19 of walkway 16. Such afork 36 forms a fork lift for vehicle 13 and is of a size to engage andlift conventional pallets as is well known in the art and describedhereinabove with respect to FIGS. 1 and 2.

As shown by the dotted lines 36 in FIG. 3 and more particularly in FIG.6, fork 36 is vertically movable (actually in an arc) with respect tovehicle 13. Thus, as shown in FIG. 6, a conventional hydraulic cylinder38 or the like is fixedly connected at one end to a point on theundersurface of vehicle 13 by means of a conventional pin 39 and snapring 40. The piston rod 41 of cylinder 38 is connected by means of asnap ring 42 to a clevis 43 (see also FIG. 7). A pair of chain links 44and 45 are pivotally connected at the forward end of clevis 43 (atpoints 46 and 47, respectively). The free end of link 44 is fixedlysecured to a point 48 on the undersurface of walkway 16. The free end oflink 45 is secured at point 49 to a block 50 secured by bolts 51 or thelike to a flange member 52 integrally connected to the rear ends of fork36.

In this manner, actuation of cylinder 38 from the console 33 (theconnecting means being conventional and not shown) moves rod 41 whichpivots link 45 to raise and lower the fork 36 integrally connectedthereto.

As shown in FIGS. Sand 9, a first vehicle 13 is shown with its batteriesand battery housing removed for shipping purposes. A second vehicle 13'(primed numerals referring to like parts of vehicle 13 with 37' used forthe fork of vehicle 13') with like parts'removed, is shown loaded on topof and oriented in a reverse direction from first vehicle 13. As can beseen, the vehicles are so configured that the side rails (i.e., theportions 18' and 19' of walkway 16 of vehicle 13') of the top vehicle 13and the tines of its fork straddle the motor housing 29 of vehicle 13.In this manner, a very compact generally rectangular unit is obtainedwhich is extremely economical for shipping purposes. The two vehiclesare separated at their delivery point and the removed portions may beput back onto their respective vehicles prior to operation thereof.

It can be seen from the foregoing that I have disclosed a uniquematerial handling system and a vehicle for carrying out that system. Inaddition, I have disclosed a vehicle which can be shipped in anextremely economical manner.

FIGS. 10 and 11- illustrate a charging and guide system for the vehicle13 which takes advantage of the previously described features of theinvention. Inasmuch as the ends of the pick aisles 126 are provided withtransversely disposed shelves 134 which clear the top of vehicle 13, itis readily possible to mount overhead power wires 160, 162, and a guidewire 164 in brackets 166 (FIG. 10) attached to shelves 134 to extendlongitudinally along pick aisles 126.

The vehicle 13 may in this case be provided with collector rollers168,170 and guide sensors 172, 174 as shown in FIG. 11. The guidesensors 172, 174 are proximity sensors which cooperate with the guidewire 164 and conventional autopilot equipment (not shown) toautomatically steer the vehicle 13 along the guide wire 164 as long asit isv in the pick aisle 126.

This arrangement has the double advantage of assuring accurate guidanceof the vehicle 13 in the very tight clearance of the pick aisle, whilerelieving the picker of the necessity to walk over to the control panelbetween picks and steer the vehicle 13 from one pick station to thenext. Automatic steering in the pick aisle also permits the use of anumbilical cord 176 (FIG. 1d) through which the picker can be providedwith remote control device 178 to control the forward motion ofvehicle13 from any point on the platform 17, 18, 19.

As for the power wirearrangement, it also has a double advantage in notonly providing continuous charging for the batteries of vehicle 13 so asto avoid long charging periods for the vehicle 13 between work shifts,but also providing a convenient way of triggering (by conventional.means) an appropriate warning system in the main aisles to show that agiven pick aisle is occupied by a vehicle 13.

What is claimed is:

1. A material handling system for grocery warehouses or the like,comprising:

a. warehouse means having pick bays therein;

b. material-holding pallets disposed on the floor of said pick bays soas to form pick aisles between rows of pallets;

c. palletizing vehicle means including:

i. a plurality of wheels mounted on said vehicle;

ii. steering means operatively engaging at least one of said wheels forturning said wheels for steering said vehicle along a supportingsurface;

iii. a generally H-shaped horizontal walkway on said vehicle extendingboth across the short axis of said vehicle generally at the'midpointthereof and from the rear end of said vehicle, about both sides of saidsteering means and terminating at the forward end of said vehicle withat least a portion thereof in front of said steering means whereby anoperator may walk almost completely about the periphery of the uppersurface 1 of said vehicle and across said vehicle, said steering meansoccupying the area in the center of said vehicle immediately forward ofthe crossbar of the H of said generally l-I-shaped walkway, and a cutoutarea being disposed in the center of said vehicle immediately rearwardof the crossbar of the H of said generally I-I-shaped walkway;

iv. fork lift means carried by said vehicle disposed below said walkwayfor engaging a pallet and lifting said pallet with respect to saidvehicle, said fork lift means including a fork having a pair of spacedfork tines extending outwardly past the rear of said vehicle and withinsaid cutout area of said walkway;

d. said aisles being of a width substantially equal to the width of saidplatform means so that a picker can reach said material held by saidpallets without leaving said platform; and

e. material in said pick bays being placed on floorsupported palletsonly and being stacked thereon to a height from said floor no greaterthan the reach of said picker plus the height above said floor of saidplatform.

2. A material handling system according to claim 1, in which saidplatform means have portions disposed between said pallet supportingmeans and said floorsupported pallets when said vehicle is positioned insaid aisle, said portions of said platform means being of a width notsubstantially greater than that required for a picker to walk and turnaround thereon.

3. A material handling system according to claim 2,

1. A material handling system for grocery warehouses or the like,comprising: a. warehouse means having pick bays therein; b.material-holding pallets disposed on the floor of said pick bays so asto form pick aisles between rows of pallets; c. palletizing vehiclemeans including: i. a plurality of wheels mounted on said vehicle; ii.steering means operatively engaging at least one of said wheels forturning said wheels for steering said vehicle along a supportingsurface; iii. a generally H-shaped horizontal walkway on said vehicleextending both across the short axis of said vehicle generally at themidpoint thereof and from the rear end of said vehicle, about both sidesof said steering means and terminating at the forward end of saidvehicle with at least a portion thereof in front of said steering meanswhereby an operator may walk almost completely about the periphery ofthe upper surface of said vehicle and across said vehicle, said steeringmeans occupying the area in the center of said vehicle immediatelyforward of the crossbar of the H of said generally H-shaped walkway, anda cutout area being disposed in the center of said vehicle immediatelyrearward of the crossbar of the H of said generally H-shaped walkway;iv. fork lift means carried by said vehicle disposed below said walkwayfor engaging a pallet and lifting said pallet with respect to saidvehicle, said fork lift means including a fork having a pair of spacedfork tines extending outwardly past the rear of said vehicle and withinsaid cutout area of said walkway; d. said aisles being of a widthsubstantially equal to the width of said platform means so that a pickercan reach said material held by said pallets without leaving saidplatform; and e. material in said pick bays being placed onfloor-supported pallets only and being stacked thereon to a height fromsaid floor no greater than the reach of said picker plus the heightabove said floor of said platform.
 2. A material handling systemaccording to claim 1, in which said platform means have portionsdisposed between said pallet supporting means and said floor-supportedpallets when said vehicle is positioned in said aisle, said portions ofsaid platform means being of a width not substantially greater than thatrequired for a picker to walk and turn around thereon.
 3. A materialhandling system according to claim 2, in which said platform meansinclude additionally elevated pad means in portions of said platformmeans adjacent to said floor-supported pallets when said vehicle ispositioned in said aisle.
 4. The system of claim 1, in which said cutoutarea is substantially unobstructedly accessible from said H-shapedwalkway on three adjacent sides including the side formed by thecross-baR of the H.
 5. The system of claim 1, in which said steeringmeans and said cutout area are substantially unobstructedly accessiblefrom the portion of said H-shaped walkway formed by the crossbar of theH.